Question 914387
x=amount invested at eight percent
y=amount invested at twelve percent
z=amount invested at ten percent
x=2y
x+y+z=210,000
3y+z=210,000
z=210,000-3y
.08x+.12y+.1z=20,200
.08x+.12y+.1(210,000-3y)=20,200
.08x+.12y+21,000-.3y=20,200
.16y+.12y-.3y=-800
-.02y=-800
y=40,000
z=210,000-120,000
z=90,000
x=80,000
.08*80,000=6,400 annual income for eight percent
.1*90,000=9,000 annual income for ten percent
.12*40,000=4,800 annual income for twelve percent